Complementary metal-oxide-semiconductor (CMOS) can be utilized for constructing integrated circuits and devices for example microprocessors, microcontrollers, static RAM, and other digital logic circuits. CMOS technology can also be employed in the field communication for manufacturing several analog circuits such as image sensors (CMOS sensor), data converters, and highly integrated transceivers. Multilevel thin film processing, global planarization and advanced photolithography techniques utilized in CMOS processing enables the ability to integrate complimentary electronic and photonic components within a single CMOS process flow.
Silicon-On-Insulator (SOI) structures may be used to fabricate various photonic devices such as optical waveguides over a silicon substrate and to integrate silicon electronics such as CMOS circuits on the same silicon platform with the photonic devices. Waveguides are frequently used in electronic/photonic processes. A slotted waveguide is a waveguide that is used as an antenna in microwave radar applications. A slotted waveguide has no reflector but emits directly through the slots. The spacing of the slots is critical and is a multiple of the wavelength used for transmission and reception. Integration of such silicon-based structures, devices and materials with photonic devices and elements that generate, guide, control, modulate, or detect light has been under extensive research and development. A need therefore exists for an improved method to integrate a slotted waveguide into a CMOS process.